Sulfur halogenated cutting oil and process of making

ABSTRACT

A naphthenic base mineral oil, useful as a cutting or lubricating oil, by itself or upon dilution, is formed by treating a naphtene base crude oil fraction with an amount of sulfuric acid less than the maximum amount required to react completely with the oil, and thereafter treating this unneutralized acid oil with a sulfur halide at ambient temperature to incorporate both sulfur and halogen into the oil whereby anti-weld properties are obtained.

United States Patent [191 Dinsmore et al.

[111 3,852,20 [451 Dec.3, 1974 SULFUR HALOGENATED CUTTING OIL ANDPROCESS OF MAKING Inventors: Robert L. Dinsmore, Long Beach;

Herbert D. Ivey, Pasadena, bothof Calif.

Lubrication Company of America, Los Angeles, Calif.

Filed: Sept. 10, 1973 Appl. No.: 395,742

Assignee:

U.S. CI 252/483, 252/45, 260/139 Int. Cl Cl0m l/38 Field of Search252/488, 45; 260/139 I References Cited UNITED STATES PATENTS 6/1946Signaigo 260/139 3/1967 Hanna et al. 252/42.4

OTHER PUBLICATIONS Gruse et a1. Chemical Technology of Petroleum, 2ndEdn. (1942), pages 6 & 7.

Primary Examiner W. Cannon Attorney, Agent, or Firm-Charles G.Lyonamount of sulfuric acid less than the maximum amount required toreact completely with the oil, and thereafter treating thisunneutralized acid oil with a sulfur halide at ambient temperature toincorporate both sulfur and halogen into the oil whereby anti-weldproperties are obtained. 1

14 Claims, No Drawings SULFUR HALOGENATED CUTTING OIL AND PROCESS OFMAKING BACKGROUND OF THE INVENTION This invention generally relates tocutting and lubricating oils, and more particularly to a process ofmaking sulfurchlorinated naphthenic oils having anti-weld properties. I

Cutting oils used in the machining of steel and like metals requireanti-weld properties to prevent the binding up of the machining metalwith the'workpiece. An anti-weld lubricant is especially required withsoft metals for the making of deep cuts where the workpiece may approachits welding temperature. Ideally, a lubrieating oil having anti-weldproperties reacts with the tool and work surfaces just below the weldtemperature to prevent the two from welding together. Such antiweldlubricating oils are usually made up of sulfur compounds which form aniron sulfide with the tool and work surface below the weld temperatureto prevent these surfaces from weldingtogether;

The effectiveness of a sulfur-containing anti-weld lubricating oil isoften dependent upon the amount of sulfur which is available to reactjust below the weld temperature; Generally, sulfonated fats, esters andwaxes have tightly bound sulfur atoms which will not readily react belowthe weld temperature unless also exposed to extreme pressure.Consequently, such materials as sulfonated fats and esters find theiruse as extreme pressure additives rather than anti-weld additives inlubricating oils. v i I On the other hand, incorporation of looselybound sulfur atoms into a cutting oil, so that the sulfur atoms areactive-at room temperature may result in corrosion of workpieces andtools. Also, free sulfurmay result in instability of the oil'itself.Thus, the ideal sulfurized cutting oil is one whichis inactive underambient conditions, but which exhibits anti-weld properties at atemperature below the welding temperature of the workpiece.

-In US. Pat. No. 3,309,315 assigned to the same assignee as the presentinvention, it was discovered that by selection of a mildly orincompletely acid treated neutralized naphthenic mineral oil andpreferably the lubricating oil fraction of such oil, a highconcentration of sulfur useful to impart anti-weld properties could beintroduced into the oil by reaction with a sulfur halide. Typically, aboiling fraction of naphthene base crude oil (also called asphalt basecrude, California or Western crude, Gulf crude, Coastal crude, etc.)boiling between 300- 1 500F and preferably the lubricating fractionbetween 500 and 760F, is incompletely reacted with sulfuric acid toremove unwanted nitrogen, oxygen and sulfur bearing compounds, etc.which will form sludge upon reactionwith S Cl if not removed. Theinsoluble products of this sulfuric -acid reaction, commonly known asgreen acid, is removed by settling, filtering or other techniques.It'was also believed that soluble reaction products, generally in theform of sulfonic acid derivatives and commonly called red or mahoganyacids, had to be removed or neutralized before the product could beutilized as a lubricating oil, since soluble red acids inthe finalproduct may cause instability of the oil, corrosion of the workpiece andstaining due to the extremely dark color.

Removal of the oil soluble red acids is generally accomplished bycontacting it with a material such as filtering clay onto which the acidwill be adsorbed. Alternately, the acid may be neutralized by treatmentwith a base. We have now discovered that neutralization or removal ofthe soluble red acids is not only unnecessary prior to sulfur halidetreatment for the making of a stable, non-corrosive anti-weld lubricant,but in fact appears to catalyze or take part in the sulfur halidereaction to give a stable sulfurchlorinated oil which releases a largenumber of sulfur atoms just below the welding temperature of the metalso as to act as an improved anti-weld lubricant. Thus, the advantages ofthis cutting oil and the process of making it is not only a costsavingsby the elimination of a costly neutralization or separation step,but also an improved anti-weld lubricant is obtained.

. SUMMARY OF THE INVENTION A naphthenic base crude oil fraction, boilingbetween 350-1,500F. with a viscosity index below 50,

is treated with 0.1 percent w. to 10 percent w. of sulfuric acid tocause separation of unwantedimpurities, but yet leave the naphthene basederivatives substantially unreacted. The unneutralized, acid-treated oilis then further reacted with a normally liquid sulfur halide, such assulfur monochloride atambient temperature for a time sufficient to give,after separation of any resulting precipitate and gaseous halide,,astable and homogeneous oil characterized by lack of offensive odor andcontaining up to l8percent w. of total sulfur and up to 5 percent w.total halide. The final product has a substantial 18 percent w. ofsulfur and halogen active below the weld temperature and is compatiblewith other lubricating oils.

PREFERRED EMBODIMENT crude oils which are considerably more paraffmic.For

many applications, a high naphthenic content isundesirable and istherefore extracted by well-known processes. Such extraction may beaccomplished by treatment with furfurol duosol (phenylpropane), 'sulfurdioxide, or sulfuric acid. In the case of sulfuricv acid, if excess acidis used to completely react with all the reactive components of the oil,awhite or pale mineral oil will be obtained. Such an oil cannot besulfurized, thereby prohibiting its use as an anti-weld cutting oil. Onthe other hand, it is desirable for many applications to have the majorcomponent of the oil a white oil, pale oil or paraffin oil. Thus, in theformulation of an antioxygen and sulfur containing compounds areremoved.

Additionally, soluble sulfonic acid derivatives, commonly called red ormahogany acids are formed. After separation of the insoluble (greenacid) reaction products of the sulfuric acid treatment, the oil isdirectly treated at ambient temperatures, with a sulfur halide.

The final product possesses some very unusual characteristics.Unexpectedly, there is little, if any, sulfonic red acid in the finalproduct. The oil contains relatively small portions of active sulfur orchlorine at room temperature, but yet exhibits excellent anti-weldproperties in the cutting of soft metals, indicating the release of boththe sulfur and chlorine, analyzed to be present, below the weldtemperature.

Although the reaction is not fully understood, it is believed that the SCl when reacted in the presence of sulfonic acids at preferably ambienttemperatures, forms a sulfur chlorinated oil of the general formula R-S-Cl or R-S-S-Cl. This is very different from other sulfur-chlorinatedproducts such as fats or waxes which release sulfur or chlorine onlyunder extreme pressure. The extreme pressure is necessary since thesuflur and chlorine are tightly bound to the carbon backbone by, forexample, the saturation of the double bonds. In the present process,sulfur chlorination is not accomplished by double bond saturation. Onthe other hand, by neutralization or removal of the sulfonic acids, itis very difficult to chlorinate the oil. Thus, upon reaction with sulfurmonochloride, an oil of the general formula R-S-S-R is obtained, withthe chlorine being released in the form of HCl, This oil will readilyrelease sulfur at temperatures well below the weld temperature of evensoft metals. This results in unnecessary corrosion and prematurespending of the anti-weld ingredient, since the weld temperature may notbe approached for many cutting applications.

In the process of this invention, a liquid crude oil fraction whichpossesses any useful lubricating qualities and generally boiling between350l,500F (after removal of tar or gasoline and naptha portions) or,only the lubricating oil fraction, boiling between 500 and 760F, may besulfurchlorinated. if the entire liquid crude oil is firstsulfurchlorinated, it may be later separated into individual fractionsin which the 500F to 760F fraction would give the most preferred cuttingoil.

, Alternatively, the entire unfractionated sulfurchlorinated oil or afractionated portion thereof may be blended with higher or lower boilingoils to give the most desired boiling range. Also, the sulfurized oilsmay be blended with other lubricating oils to give the desired viscosityand viscosity index. Since the product of this invention may be blended.with pale oils, white oils or paraffin oils, boiling range, viscosityand viscosity index may be tailored for'each application.

The unneutralized sulfuric acid-treated riaphthenic oil-is treated withanormally liquid sulfur halide to form the sulfurchlorinated cutting oil.Although sulfurchlorination is preferable, any sulfur halide capable ofreacting with the oil to form a product having anti-weld properties maybe used. These may include sulfur monochloride, sulfur dichloride,sulfur monobromide, thionyl chloride, sulfuryl chloride, or other sulfurhalides which are liquid under ambient conditions and which will reactwith the naphthenic oil. We have generally found that up to 26 percentby weight of sulfur monochloride may be reacted with an unneutralizedacidtreated naphthenic base oil fraction, boiling between 500 to 760F.The final product may contain up to 13 percent active sulfur and up to18 percent total sulfur as well as up to chlorine after removal of allthe hydrogen chloride. Despite the presence of chlorine and sulfur inthe final product, the oil exhibits little staining or corrosion at roomtemperatures. However, when used as a cutting oil, it has been found toexhibit extremely effective anti-weld properties, indicating that thesulfur and chlorine compounds, which are relatively inactive at roomtemperature, will react below the welding temperature to prevent thewelding of the tool surface with the workpiece.

Also, although it is believed that the sulfonic red acids catalyze thesulfur halide reaction, reaction in the presence of a metal such as ironfilings or in an iron ket tle reaction vessel may be desired to furtherspeed the reaction.

EXAMPLE I A naphthenic base, straight run, Western mineral oil having adistillation range of about 500 to about 760F, a viscosity index below50, and a pour point below 30F is agitated with l 10 vol. concentratedsulfuric acid at room temperature for minutes and then allowed to settlefor 4 hours, after which the precipitate is removed.

To 800 gms of this oil is reacted a total of 210 gms (26 percent byweight) of S Cl gms of S Cl is first added to the oil in an iron kettlereaction vessel at ambient temperature with agitation by bubbling airtherethrough. The iron kettle and in addition, iron filings may be usedto catalyze the reaction, although it is preferable not to catalyze thereaction so as to minimize the exotherm and permit the chlorine toreact. It is believed that if the reaction is allowed to proceed wellabove ambient temperature, the chlorine will be driven off as HCl andwill not react with the oil. The reaction is allowed to proceedovernight, and the second day, an additional 105 gms of S Cl is addedwith air agitation. The reaction is allowed to proceed to completion fora total reaction time of about 48 hours. The end of the reaction isindicated by the absence of sulfur monochloride odor in the effluentvapor.

The kettle is then heated to -200F with air blowing for about 10 hoursto' remove unreacted chlorine in the form of HCl gas. The oil is letstand. overnight and filtered to remove any precipitate. The resultantproduct isa dark reddish colored, sulfurized and chlorinated mineral oilof pleasant odor, stably homogeneous, soluble in white oil and posessingthe following characteristics:

Gravity APl 12.6 Lbs per gallon 8.18 Specific Gravity at 60F 0.9820Density at l5F 0.98 [4 Viscosity SU at l00F 209 Viscosity CS at l00F45.0

Pour Point degrees F +15 Flash Point COC degrees F 325 Copper StripCorrosion at 77F g Positive Total Sulfur wt 8.76

ASTM D129 Active Sulfur wt 6.49

Ford Motor Co. Method ATl-l Total Chlorine wt 1.24

ASTM D808 Soluble in pale or paraffin oil EXAMPLE II A cutting oil wasblended from 25 percent w. of the oil of Example I with 75 percent w. ofa mineral oil t 100 SU at 100F). When used in threading steel pipe,bright shiny threads with smooth surfaces were obtained, with tool life40 times longer than commercial mixtures of pale oil and sulfurizedfatty oil.

Since the product of this invention has been found to exhibit equal orsuperior anti-weld properties as compared with a product made fromneutralized sulfuric acid-treated naphthenic based oil, it would beunderstood that the product of this invention may be used for a widevariety of applications, such as those taught in U.S. Pat. No. 3,309,315which discloses a neutralized sulfuric oil. Such applications mayinclude use as a cutting oil, alone or as an additive. It may be usedfor threading steel pipe, as a gear oil, machining, and drilling,especially in the drilling of oil wells.

What is claimed is:

l. The process which comprises reacting a naphthenic-base mineral oil,boiling between 350- 1,500Fwith about 0.1 percent w. of sulfuric acid,such amount of sulfuric acid being less than the maximum amount requiredto react completely with the oil, removing the sludge formed thereby,reacting the unneutralized product with a normally liquid, sulfurhalide, and separating the resulting precipitate and hydrogen halidetherefrom, to leave a stable and homogeneous oil characterized by lackof offensive odor and containing up to about 18 percent w. of totalsulfur and up to about 5 percent w. total halide in oil soluble organiccompounds which have anti-weld properties.

2. The process of claim 1 wherein the sulfur halide is essentiallysulfur monochloride.

3. The process which comprises reacting the lubricating oil fraction ofa naphthenic base mineral oil with about 0.1 percent w. to about percentw. of sulfuric acid, such amount of sulfuric acid being less than themaximum amount required to react completely with the oil, removing thesludge formed thereby, reacting the unneutralized product with anormally liquid sulfur halide, separating the resulting precipitate andhydrogen halide therefrom to leave a stable and homogeneous oilcharacterized by lack of offensive odor and containing up to about 18percent w. of total sulfur and up to 5 percent w. of total halide in oilsoluble organic compounds which have anti-weld properties, whereby thebulk of said oil containing said soluble compounds may be used as acutting oil by itself or upon dilution.

4. The process of claim 3 wherein said lubricating oil fraction boilsbetween 500 and 760F and exhibits a viscosity index below 50.

5. The process which comprises reacting a naphthenic base mineral oilboiling between 350-1,500F and having a viscosity index below about 50with about 0.1 percent w. to about 10 percent w. of sulfuric acid, suchamount of sulfuric acid being less than the maximum amount required toreact completely with the oil, removing the sludge formed thereby,reacting the unneutralized product with a normally liquid, sulfur halideat ambient room temperature, and separating the resulting precipitateand hydrogen halide therefrom to leave a stable and homogeneous oilcharacterized by lack of offensive odor and containing up to about 18percent w. of total sulfur and 5 percent w. of halide in oil solubleorganic compounds which have anti-weld properties.

6. The process of claim 5 wherein said sulfuric acid is about 0.5percent w. to about 5 percent w. and said sulfur halide is added isfractional amounts during an extended period of time up to about 15hours and said a reaction is effected principally at about ambienttemperatures with agitation effected by passage of an air currentthrough the reaction mixture until no odor of sulfur halide or hydrogenhalide is evident, even upon heating to about 200F.

7. The process of claim 6 wherein the reaction proceeds for about 48hours.

8. The process of claim 6 wherein said sulfur halide is essentiallyabout 0.5 percent w. to about 26 percent w. of sulfur monochloride.

9. The process which comprises reacting the lubricating oil fraction ofa naphthenic base mineral oil with about 0.5 percent w. to about 5percent w. of sulfuric acid, such amount of sulfuric acid being lessthan the maximum amount required to react completely with the oil,removing the sludge formed thereby, reacting it at ambient temperaturewith up to about 26 percent w. of sulfur monochloride, and separatingthe resulting precipitate and volatile chlorides therefrom to leave astable and homogeneous cutting oil or additivetherefor, characterized bylack of offensive odor and containing up to about 18 percent w. of totalsulfur and up to about 5 percent total chlorine in oil soluble organiccompounds which have anti-weld properties.

10. A mineral oil base, cutting fluid containing homogeneously andstably disbursed therein an anti-weld quantity of the organic oilsoluble reaction product formed between a normally liquid, sulfur halideand a naphthenic base mineral oil boiling between 350l,500F and having aviscosity index below 50, said reaction product being formed by treatingsaid mineral oil with about 0.1 percent w. to about l0 percent w. ofsulfuric acid, such amount of sulfuric acid being less than the maximumamount required to react completely with the oil, removing the sludgeformed by the sulfuric acid and then reacting the oil with said normallyliquid sulfur halide and separating the resulting precipitate therefrom,thereby leaving an organic oil soluble reaction product containing up toabout 18 percent w. total sulfur and up to 5 percent w. total halogenhaving anti-weld properties, said reaction product remaining dissolvedin the mineral oil in which it.was formed, which oil forms the bulk ofsaid cutting fluid.

thenic base mineral oil, prior to saidsulfuric acid treatment, consistsessentially of a lubricating oil fraction of said mineral oil boilingbetween 500 and 760Ff 14. A fluid composition having lubricant andantiweld properties having uniformly disbursed therein abeneficialquantity of the reacted mineral oil of claim 10.

1. THE PROCESS WHICH COMPRISES A NAPHTHENIC-BASE MINERAL OIL, BOILINGBETWEEN 350*- 1,500F WITH ABOUT 0.1 PERCENT W. OF SULFURIC ACID, SUCHAMOUNT OF SULFONIC ACID BEING LESS THAN THE MAXIMUM AMOUNT REQUIRED TOREACT COMPLETELY WITH THE OIL, REMOVING THE SLUDGE FORMED THEREBY,REACTING THE UNNEURALIZED PRODUCT WITH A NORMALLY LIQUID, SULFUR HALIDE,AND SEPARATING THE RESULTING PRECIPITATE AND HYDROGEN HALIDE THEREFROM,TO LEAVE A STABLE AND HOMOGENEOUS OIL CHARACTERIZED BY LACK OF OFFENSIVEODOR AND CONTAINING UP TO ABOUT 18 PERCENT W. OF TOTAL SULFUR AND UP TOABOUT 5 PERCENT W. TOTAL HALIDE IN OIL SOLUBLE ORGANIC COMPOUNDS WHICHHAVE ANTI-WELD PROPERTIES.
 2. The process of claim 1 wherein the sulfurhalide is essentially sulfur monochloride.
 3. The process whichcomprises reacting the lubricating oil fraction of a naphthenic basemineral oil with about 0.1 percent w. to about 10 percent w. of sulfuricacid, such amount of sulfuric acid being less than the maximum amountrequired to react completely with the oil, removing the sludge formedthereby, reacting the unneutralized product with a normally liquidsulfur halide, separating the resulting precipitate and hydrogen halidetherefrom to leave a stable and homogeneous oil characterized by lack ofoffensive odor and containing up to about 18 percent w. of total sulfurand up to 5 percent w. of total halide in oil soluble organic compoundswhich have anti-weld properties, whereby the bulk of said oil containingsaid soluble compounds may be used as a cutting oil by itself or upondilution.
 4. The process of claim 3 wherein said lubricating oilfraction boils between 500* and 760*F and exhibits a viscosity indexbelow
 50. 5. The process which comprises reacting a naphthenic basemineral oil boiling between 350*-1,500*F and having a viscosity indexbelow about 50 with about 0.1 percent w. to about 10 percent w. ofsulfuric acid, such amount of sulfuric acid being less than the maximumamount required to react completely with the oil, removing the sludgeformed thereby, reacting the unneutralized product with a normallyliquid, sulfur halide at ambient room temperature, and separating theresulting precipitate and hydrogen halide therefrom to leave a stableand homogeneous oil characterized by lack of offensive odor andcontaining up to about 18 percent w. of total sulfur and 5 percent w. ofhalide in oil soluble organic compounds which have anti-weld properties.6. The process of claim 5 wherein said sulfuric acid is about 0.5percent w. to about 5 percent w. and said sulfur halide is added isfractional amounts during an extended period of time up to about 15hours and said reaction is effected principally at about ambienttemperatures with agitation effected by passage of an air currentthrough the reaction mixture until no odor of sulfur halide or hydrogenhalide is evident, even upon heating to about 200*F.
 7. The process ofclaim 6 wherein the reaction proceeds for about 48 hours.
 8. The processof claim 6 wherein said sulfur halide is essentially about 0.5 percentw. to about 26 percent w. of sulfur monochloride.
 9. The process whichcomprises reacting the lubricating oil fraction of a naphthenic basemineral oil with about 0.5 percent w. to about 5 percent w. of sulfuricacid, such amount of sulfuric acid being less than the maximum amountrequired to react completely with the oil, removing the sludge formedthereby, reacting it at ambient temperature with up to about 26 percentw. of sulfur monochloride, and separating the resulting precipitate andvolatile chlorides therefrom to leave a stable and homogeneous cuttingoil or additive therefor, characterized by lack of offensive odor andcontaining up to about 18 percent w. of total sulfur and up to about 5percent total chlorine in oil soluble organic compounds which haveanti-weld properties.
 10. A mineral oil base, cutting fluid containinghomogeneously and stably disbursed therein an anti-weld quantity of theorganic oil soluble reaction product formed between a normally liquid,sulfur halide and a naphthenic base mineral oil boiling between350*-1,500*F and having a viscosity index below 50, said reactionproduct being formed by treating said mineral oil with about 0.1 percentw. to about 10 percent w. of sulfuric acid, such amount of sulfuric acidbeing less than the Maximum amount required to react completely with theoil, removing the sludge formed by the sulfuric acid and then reactingthe oil with said normally liquid sulfur halide and separating theresulting precipitate therefrom, thereby leaving an organic oil solublereaction product containing up to about 18 percent w. total sulfur andup to 5 percent w. total halogen having anti-weld properties, saidreaction product remaining dissolved in the mineral oil in which it wasformed, which oil forms the bulk of said cutting fluid.
 11. The cuttingfluid of claim 10 wherein said normally liquid sulfur halide consistsessentially of sulfur monochloride and said reaction product containsfrom about 4 percent w. up to about 18 percent w. of total sulfur andfrom about 0.5 percent w. to about 5 percent w. total chlorine.
 12. Thecutting fluid of claim 11 wherein said reaction product is formedessentially at ambient temperature.
 13. The cutting fluid of claim 10wherein said naphthenic base mineral oil, prior to said sulfuric acidtreatment, consists essentially of a lubricating oil fraction of saidmineral oil boiling between 500* and 760*F.
 14. A fluid compositionhaving lubricant and anti-weld properties having uniformly disbursedtherein a beneficial quantity of the reacted mineral oil of claim 10.